Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 271835 AFDLWX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 235 PM EDT MON OCT 27 2014 .SYNOPSIS... HIGH PRESSURE WILL MOVE OFF TO THE EAST TODAY THROUGH TUESDAY. A COLD FRONT WILL PASS THROUGH THE AREA WEDNESDAY AND HIGH PRESSURE WILL RETURN FOR THURSDAY AND FRIDAY. ANOTHER COLD FRONT WILL PASS THROUGH THE AREA FRIDAY NIGHT AND CANADIAN HIGH PRESSURE WILL BUILD OVERHEAD DURING THE WEEKEND. && .NEAR TERM /THROUGH TUESDAY/...
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HIGH PRESSURE IS LOCATED ACROSS THE MID-ATLANTIC THIS AFTERNOON. A FEW PASSING CIRRUS HAVE BEEN OBSERVED BUT FOR THE MOST PART THE AREA IS CLEAR. LIGHT SOUTHERLY FLOW WILL CONTINUE TODAY AND TEMPERATURES WILL CONTINUE TO RISE INTO THE UPPER 60S TO LOW 70S. THE AIRMASS IS VERY DRY AND LIGHT MIXING HAS RESULTED IN DEWPTS IN THE 30S AS WELL AS RH VALUES. HIGH PRESSURE WILL MOVE TO THE EAST AND OFF THE EAST COAST TONIGHT WHILE LIGHT SOUTHERLY FLOW PERSISTS. AN UPPER LEVEL RIDGE AXIS WILL MOVE OVERHEAD LATE TONIGHT AND SOUTHERLY FLOW ALOFT WILL INCREASE. PLENTY OF SUNSHINE AND WAA IS EXPECTED TUESDAY WITH TEMPS REACHING THE UPPER 70S TO AROUND 80 WHICH IS 10-15 DEG ABOVE NORMAL FOR LATE OCTOBER.
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&& .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
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AN UPPER LEVEL TROUGH WILL APPROACH THE GREAT LAKES TUESDAY NIGHT. A DEEP SFC LOW WILL BE RETREATING TOWARDS HUDSON BAY WHILE A COLD FRONT APPROACHES FROM THE OHIO VALLEY. A CONFINED AREA OF MOISTURE WITH THE COLD FRONT IS EXPECTED TO MOVE INTO THE POTOMAC HIGHLANDS BY LATE TUESDAY NIGHT. IT WILL MAKE A EASTWARD PROJECTION ACROSS THE MID-ATLANTIC THROUGH WEDNESDAY MORNING. SHOWERS ARE EXPECTED ALONG THE FRONT BUT AMTS SHOULD BE LESS THAN A QUARTER INCH. THE COLD FRONT WILL MOVE INTO SOUTHERN VA BY WED AFTERNOON. DRIER AIR WILL MOVE INTO THE MID-ATLANTIC FROM THE NORTHWEST AND CLOUDS WILL DIMINISH BY EVENING. HIGH PRESSURE WILL APPROACH FROM THE MIDWEST THURSDAY. A SHORTWAVE TROUGH WILL DROP INTO THE OHIO VALLEY THURSDAY AND CLOUDS SHOULD INCREASE FROM THE WEST THURSDAY AFTERNOON.
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&& .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
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UPPER LEVEL TROUGHING WILL AFFECT THE CWA THROUGH SUNDAY. HIGH PRESSURE RIDGING RETURNING SUNDAY. SHORTWAVE FROM CENTRAL CANADA SWEEPING INTO NEW ENGLAND BY LATE SATURDAY. WEAK SURFACE HIGH PRESSURE WILL BUILD IN FROM THE WEST ON THURSDAY. POLAR COLD FRONT IS EXPECTED TO USHER IN THE COLDEST TEMPERATURES SO FAR THIS FALL DURING THE WEEKEND. BREEZY CONDITIONS ARE POSSIBLE AS GRADIENT TIGHTENS BETWEEN HIGH APPROACHING FROM THE WEST AND LOW CENTER OVER NEW ENDLAND DURING THE LATTER HALF OF THE PERIOD. ALTHOUGH WENT HIGHER THAN DETERMINISTIC GUIDANCE FOR SATURDAY TEMPERATURES DO EXPECT WEEKEND TEMPERATURES TO BE COLDER THAN NORMAL.
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&& .AVIATION /18Z MONDAY THROUGH SATURDAY/...
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VFR CONDITIONS EXPECTED TODAY AND TONIGHT AS HIGH PRESSURE RESIDES ACROSS THE AREA. S WINDS 5-10KTS EXPECTED THIS AFTERNOON AND BECOMING LIGHT OVERNIGHT. S WINDS 10-15 KTS WITH GUSTS UP TO 20 KTS EXPECTED TUESDAY. A COLD FRONT WILL APPROACH THE MID-ATLANTIC TUESDAY AND CLOUDS WILL INCREASE FROM WEST TO EAST TUESDAY NIGHT THROUGH WEDNESDAY. SHRA ARE POSSIBLE ALONG FRONT. MVFR CONDITIONS POSSIBLE DURING THIS TIME. HIGH PRESSURE MOVES INTO THE REGION FOR THE END OF THE WORK WEEK.
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&& .MARINE...
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&& $$ SYNOPSIS...HAS NEAR TERM...HAS SHORT TERM...HAS LONG TERM...CEM AVIATION...HAS MARINE...CEM/HAS

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